Muscles and fibres

Question 1

What is irritability in muscles?

Answer 1

Ability to respond to various stimuli (e.g. force, temperature, nerve impulse)

Question 2

What is extensibility in muscles?

Answer 2

Ability to lengthen in response to stimuli

Question 3

What is elasticity in muscles?

Answer 3

Ability to stretch and return to its resting length or shape

Question 4

What is conductivity in muscles?

Answer 4

Ability to transmit nerve impulse

Question 5

What are the characteristics of smooth muscle? and example

Answer 5

-Involuntary muscle

-one nucleus

-unstriated

-Lines blood vessels & hollow organs (e.g. bladder, uterus, digestive tract)

Question 6

What are the characteristics of cardiac muscle? and example

Answer 6

-Involuntary muscle
-striation / intercalated discs
-one nuclei
-Controls heart beat
-ONLY found in heart

Question 7

What are the characteristics of skeletal muscle? and example

Answer 7

-voluntary muscle

-striated

-50-40% of body weight

-multi nucleated cells (e.g. biceps, deltoids)

Question 8

*fibre arrangements *
What are longitudinal muscle fibres?

Answer 8

Parallel fibres with short tendon.

Example: Abdominals

Question 9

*fibre arrangements *
What are fusiform muscle fibres?

Answer 9

Spindle-shaped fibres

Example: Biceps brachii

Question 10

*fibre arrangements *
What are radiate muscle fibres?

Answer 10

Fan-shaped fibres

Example: Pectoralis major

Question 11

*fibre arrangements *
What are penniform muscle fibres?

Answer 11

Fibres arranged at oblique angles

Example: Deltoids

Question 12

what does unipennate mean?

Answer 12

Muscle fibres are on one side of the tendon

Question 13

what does binpennate mean?

Answer 13

Muscle fibres are on both sides of a central tendon

Question 14

what does multipennate mean?

Answer 14

Muscle fibres are in multiple rows with several tendons

Question 15

What are sarcomeres and what do they contain?

Answer 15

the functional unit of skeletal muscle cells
contain: myofilaments